SELECTED CHITONS
OF ASIA, JAPAN &
PACIFIC REGION
Descriptions and ranges taken from Monograph of Living Chitons by Piet Kaas and Richard A. VanBelle (5 volumes), 1985-1994 and/or Studies on Chitons of Mutsu Bay with General Discussion on Chitons of Japan by Isao Taki, 1937 and/or Loricates of the Philippines by Estrella Z. Ang, 1967
CLICK ON THUMBNAIL IMAGE TO VIEW LARGER IMAGE
Schizoplax brandtii (von Middendorff, 1847)
ISCHNOCHITONIDAE
Range: North Pacific
This two-thirds inch chiton has a narrow girdle, closely beset with minute spines but appearing almost smooth to the naked eye. Entire surface smooth but under a lens the valves are finely granulated in quincunx. The lateral areas are scarcely defined. The valve color is olive-brown, streaked, maculated or clouded with blue or chestnut (taken from Pilsbry's Manual of Conchology).
Tonicella lineata (Wood, 1815) - see West Coast chitons
Tonicella marmorea (Fabricius, 1780) - see East Coast chitons
Ischnochiton boninensis Bergenhayn, 1933
ISCHNOCHITONIDAE
Range: Japan
This one and a quarter inch chiton is elongate oval in shape and moderately elevated. The color of the valves is olivaceous to blackish green, mostly blotched or streaked with dirty white or light pink. Valves sculptured with about fifty bifurcating, flat, radiating riblets, separated by very fine grooves.The girdle is covered with small scales and greyish brown in color, often with yellowish blotches or bands.
>
Ischnochiton (Haploplax) comptus (Gould, 1859)
ISCHNOCHITONIDAE
Range: Japan
This one inch elongate chiton has broad valves which are mostly light greyish brown. They can be variously blotched with white, cream, pink, reddish chestnut or blackish brown. Some specimens are olivaceous mottled with white. Valve surface is evenly microgranulose, sculptured with numerous weak, glossy, radiating riblets. The girdle is scaly and colored in alternating yellowish and greyish or brownish bands.
Ischnochiton hakodadensis Carpenter in Pilsbry, 1893
ISCHNOCHITONIDAE
Range: Japan
This one inch chiton is elongate oval in shape and moderately elevated. The valve color is predominately slate-blue, dark olive-grey or dark greyish brown with blotches of creamy white. Central areas minutely pitted in a chevron-like or quincuncial pattern. Lateral areas slightly raised, clearly marked and sculptured with flat, radiating costae. The girdle is narrow and colored like the valves, sometimes with alternating bands of lighter and darker tones. It is covered with imbricating scales.
Stenoplax petaloides (Gould, 1846)
ISCHNOCHITONIDAE
Range: Hawaii
This small, one-third inch chiton, is elongate oval in shape and moderately elevated. The valve color is whitish to very light beige with a pattern of dark streaks, splotches of orange-red and scattered, round, bright, ultramarine spots. Sometimes a specimen can be completely white or bluish-bblack, bluish-black with a white stripe along the dorsal or have a zebra stripes pattern of alternating pinkish and reddish-brown bands. The girdle is moderate wide and whitish in color, irregularly blotched with light to dark green, covered with small, overlapping scales.
Lepidozona (Tripolax) albrechtii (von Schrenck, 1862)
ISCHNOCHITONIDAE
Range: Japan
This handsome two inch chiton is oval in shape and moderately elevated. The color of the valves is reddish, maculated with dark brown or black or occasionally bloched with creamy white. The lateral areas are sculptured wwith many, mostly bifurcating, low, radiating ribs, bearing sparse, minute, glossy pustles. The central areas have up to sixty five, longitudinal riblets. The girdle is moderately wide, colored in alternating bands of dark reddish brown and yellowish. It is covered with large, loosely imbricating, almost smooth scales.
Lepidozona coreanica (Reeve, 1847)
ISCHNOCHITONIDAE
Range: Japan
This one and one-half inch chiton is oval to elongate oval in shape and is moderately elevated. The valves are generally yellowish brown or greenish in color blotched with dark brown or dark green. The lateral areas are distinctly raised and sculptured with low radial ribs, some bifurcating towards the outer margin. Each rib ornamented with medium to large, roundish pustules. The central areas are finely, longitudinally, granosely ridged with twenty to twenty-five ridges per side. The girdle has alternating bands of light yellowish and dark greenish brown color and is covered with rather large, slightly bent scales.
Plaxiphora (Mercatora) mercatoris Leloup, 1936
MOPALIIDAE
Range: Easter Island
This two inch chiton is deep bluish-green with a dorsal that is blotched and/or streaked with pale olivaceous and reddish to blackish brown. The girdle is of moderate width, fleshy and dark grayish brown. It is covered with numerous, randomly dispersed, neatly separated, stout, yellowish ringed bristles.
Mopalia retifera Thiele, 1909
MOPALIIDAE
Range: Japan, Western North Pacific
This one and one-half inch elongated oval chiton has variable colored valves. They can be whitish with dark green or blackish brown flecks, light gray with a yellowish green tinge and brown spots, brownish with dark brown stripes or red, orange, yellow, green mottled with irregular spots of various colors. The girdle is of moderate width, light brown in color with darker bands. It is covered with minute, blunt or pointed spicules and some small isolated bristles, and setae of various sizes.
Mopalia schrencki Thiele, 1908
MOPALIIDAE
Range: Sea of Japan (coast of USSR), Hokkaido, Southern Kurile Islands, and Korea
This one inch oval chiton has a moderately elevated dorsal ridge. The color of the valves is dark yellow, orange, olive-green or greyish brown with some white banding. The girdle is moderate width, brownish orange to light brown in color. It is covered with dense, small, smooth spicules, interspersed with setae, each one having many long, thread-like bristles.
Placiphorella atlantica (Verrill & S.I.Smith, 1882)
MOPALIIDAE
Range: Circumpolar, northern Atlantic Ocean, northern Pacific Ocean, eastern Indian Ocean.
This one and one-half inch chiton is broadly ovate. The valve colors are white, light straw-yellow or pale brown. The girdle is broadly expanded at anterior end and pale yellowish in color. It is densely covered with small, elongate, spicules and sparsely scattered large bristles covered with slender, smooth, sharp spicules.
Placiphorella borealis Pilsbry, 1893
MOPALIIDAE
Range: Northwest Pacific Ocean, Bering Island to east coast of Hokkaido.
This medium sized chiton is colored dark brown with whitish along dorsal ridge. Like all Placiphorella, the girdle is wider at anterior. It is brownish in color, densely covered with minute, slender, pointed, yellowish-brown spicules. These are sparsely interspersed with fairly thick, round bristles.
Placiphorella stimpsoni (Gould, 1859)
MOPALIIDAE
Range: Sea of Japan, Pacific coast of Japan from s. Hokkaido to Kyushu, and southwestern Korea.
This one inch oval shaped chiton is colored dirty white which is irregularly spotted or streaked with pink, brown, bluish-green and black. As expected the girdle is broadly extended at anterior end. The color is creamy yellow to light brown blackish bands. The surface of girdle is densely covered with minute, drop-shaped, pointed spicules, sparsely interspersed with long, smooth bristles which have long, stout brown or olivaceous spicules.
Chiton (Rhyssoplax) kurodai Is.& Iw. Taki, 1929
CHITONIDAE
Range: Japan (Pacific coast & west coast), Inland Sea, Sea of Japan
This handsome one inch chiton can be described as oval or elongate oval in shape and variable in color. The valves are well elevated. The lateral areas are well defined by being raised and smooth. The central area is sculptured with 14 to 21 longitudinal lines. The girdle is rather narrow and densely covered with imbricating scales.
Chiton (Rhyssoplax) linsleyi (Burghardt, 1973)
CHITONIDAE
Range: Hawaii
This barely one-half inch chiton appears smooth to the naked eye and pitted when viewed under low magnification. Under high magnification, it is clear the surface is indeed smooth, the 'pitted' appearance is caused by a color pattern. Lateral areas are defined but not sharply raised. They possess radiating series of bifurcating grooves as does the anterior valve. The central areas are cut longitudinally with from 10-13 sharp lines. Both lateral and central areas have the 'pitted' color pattern. The color of the valves is quite variable, ranging from a clean grey-wh9te to a mottled black and white or green and white. Some specimens are solid in color. The girdle is of medium width and is covered with fairly large, smooth scales typical of Chitonidae. The color is cream with green bands.
Acanthopleura gemmata (de Blainville, 1825)
CHITONIDAE
Range: Southeast Pacific, Philippines
This large intertidal chiton can reach four inches in length. The valves are generally eroded and five the chiton a round-backed appearance. The color is greyish-green to greyish brown. The girdle is thick, wide, often banded. It is crowded with white to dark gray, brown or black spinelets.
Liolophura japonica (Lischke, 1893)
CHITONIDAE
Range: Japan (Pacific coast & west coast), Inland Sea, Sea of Japan
This 50 mm chiton is elliptical in shape. It is broad, elevated and roundly arched. The lateral areas are hardly raised, scarcely defined. The total valve surface has nemerouss, fine, diagonally arranged granules. The valves have no luster and are blackish, generally showing a wide light stripe on each side of a black dorsal stripe. The girdle is varied with alternate patches of white and scorched brown or blackish. It is densely covered with two kinds of numerous short thick spines, becoming smaller toward the outer edge. These spines are reddish-brown or blackish tipped with light brown or cream-white.
Tonicia (Lucilina) amanda (Thiele, 1910)
CHITONIDAE
Range: Sea of Japan
This 18 mm chiton generally has rose-red colored valves. The central areas have longitudinal furrows. The lateral areas are bordered anteriorly with a series of scaly granules, posteriorly coarsely granulated. The interspace between them is nearly smooth. The girdle is covered sparsely with small, pointed, ribbed spinules.
Onithochiton hirasei Pilsbry, 1908
CHITONIDAE
Range: Japan
One of the most beautiful chitons found in Japan. Quite variable in coloration. The surface of the valves is smooth and the girdle appears nude and painted colorfully.
Acanthochitona defilippi (Tapparone-Caneri)
ACANTHOCHITONIDAE
Range: Japan
This is a moderate sized chiton. The small heart-shaped valves are somewhat covered by a wide girdle which is covered with densely set, stout, calcareous spines. The color of the girdle is black-brown sometimes banded with white. Description taken from Pilsbry's Manual of Conchology Volume XV, Acad.Nat.Sci.Phila., 1893
Acanthochitona viridis (Pease, 1872)
ACANTHOCHITONIDAE
Range: Hawaii
This ovate one and a quarter inch chiton has slightly elevated valves which greenish with a pale or whitish line down the jugal ridge. The lateral areas are not defined but are finely granulose. The girdle has a tuft of dense, vitreous and dark green spicules at each valve suture. Description taken from Pilsbry's Manual of Conchology Volume XV, Acad.Nat.Sci.Phil., 1893.